Civil and Environmental Engineering


Date of this Version

Fall 11-29-2012


A DISSERTATION Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy, Major: Civil Engineering, Under the Supervision of Professor Aemal Khattak. Lincoln, Nebraska: December, 2012

Copyright (c) 2012 ZHENG LUO


A significant number of pedestrians and bicyclists (i.e., non-motorists) use the roadway system in the U.S. Research pertaining to the safety of them, especially their safety at highway-rail grade crossings (HRGCs), has drawn much attention in the past decade, and remains an important issue of safety research. Yet, the majority of existing research has examined non-motorist safety at intersections or motorist safety at HRGCs separately. Such research has related primarily to exploring relationships between safety countermeasures (e.g., engineering devices, education, enforcement, etc.) and crash frequency/severity, using different quantitative analysis approaches. A primary limitation of these studies is that few have focused on identifying impact factors associated with non-motorist safety at HRGCs or explicit assessment of educational activity’s safety effect on non-motorist safety at HRGCs, by concentrating on undiluted effects of educational activity only.

The current research selected a two-quadrant HRGC in the City of Fremont, Nebraska for data collection. A median barrier device was installed at this HRGC in 2006. Restorative maintenance was performed from April 1st to 18th, 2011. In addition, an educational activity was implemented at this HRGC on September 29th and 30th, 2011 to explore its impact on HRGC safety. Based on these two issues, the current research consisted of data collection at the HRGC before and after maintenance, and before and after the educational activity.

Following the preliminary analysis and statistical modeling of the collected data, it was concluded that: 1) pedestrians and bicyclists could be treated as one group during analysis, defined as “non-motorists” in terms of the similarity between their crossing violation frequencies, 2) the total motorist violation frequency increased with more violation opportunities, higher traffic volume, group crossing, non-nighttime period, and more crossing trains, 3) the total non-motorist violation frequency increased with higher traffic volume, group crossing, train stoppage, non-nighttime period, and gate malfunction, 4) regarding the influence of median barrier maintenance on the motorist safety, there was no statistically significant change in motorist’s type 2 and 4 violations before and after the maintenance, 5) educational activity alone was effective toward reducing non-motorists’ type 2 violations at the HRGC during a short-term period.

Adviser: Aemal Khattak